Method of forming chain link plates



Nov. 12, 1968 R. CAIN METHOD OF FORMING CHAIN LINK PLATES Filed April25, 1966 2 Sheets-Sheet 1 R. L. CAIN Nov. 12,1968

METHOD OF FORMING CHAIN LINK PLATES 2 Sheets-Sheet 2 Filed April 25,1966 i A r l l i M hz/eniorx 1 0K211; l. Cm'n/ United States Patent O3,410,084 METHOD OF FORMING CHAIN LINK PLATES Robert L. Cain, WestLafayette, Ind., assignor to Amsted Industries Incorporated, Chicago,Ill., a corporation of New Jersey Filed Apr. 25, 1966, Ser. No. 545,121Claims. (Cl. 59-8) ABSTRACT OF THE DISCLOSURE A method of progressivelyforming wire stock into chain link plates by forming at a first station,opposed locating grooves to divide the wire into sections, and whereineach section is further formed with narrow medial portions. At a secondstation the sections are flattened and circular cavities are formedtherein. Work at the first and second stations is carried out while in amolten lead bath. The sections are quenched in oil, and at a thirdstation the circular cavities are punched to form pin holes. Thesections are separated at a forth station into individual link plates.

This invention relates to a method of forming chain link plates for usein the manufacture of link chain for power transmission and conveyingsystems.

Heretofore, it has been the practice to punch chain link plates from ametal strip and then to harden the links by special heat treatment andfinishing methods. As this method results in a scrap loss ofapproximately 30 percent, it is an object of the present invention toprovide a method for forming chain link plates in which the scrap lossis reduced to approximately one or two percent.

Briefly, the present invention comprises a method in which wire stock ismoved step-by-step through several forming dies to form a chain ofconnected link plates having pin holes therein, the link plates beingsuccessively separated from the chain of link plates at the completionof the forming operations. While the wire may be cold formed to providea chain of connected link plates, it is contemplated that the wire maybe formed in a heated condition to improve the physical properties ofthe link plates.

The invention embodies other novel features which are hereinafter setforth in the specification and claims and illustrated in theaccompanying drawings, forming part thereof, wherein:

FIGURE 1 is a schematic plan view illustrating the apparatus forprogressively forming wire stock to provide a chain of link plates whichare successively severed from the chain at the completion of the formingoperations.

FIGURE 2 is a side elevation of the apparatus shown in FIGURE 1.

FIGURE 3 is an enlarged fragmentary view illustrating the first workforming station.

FIGURE 4 is an enlarged view illustrating the second work formingstation.

FIGURE 5 is an enarged section showing the third work forming station.

FIGURE 6 is an enlarged detail view showing the shearing station.

Referring now to the drawings for a better understanding of theinvention, the apparatus for transforming chain link plates from S.A.E.4340 alloy steel round wire stock 2 is shown as comprising a furnace 3in which the wire stock is heated to a temperature of 1550 F. and thenwithdrawn from the furnace into a tank 4 containing ice molten leadmaintained at a temperature of up to approximately 1000 F.

The wire stock is moved step-by-step within the lead bath tank 4 to afirst forming station 6 and then to a second forming station 7 by meansof a conventional stock feed mechanism 8 actuated by a hydraulic powercylinder 9. The first forming station 6 comprises a forming anvil 11 andopposing forming punches 12 and 13 actuated by hydraulic cylinders 14and 16 to compress a section 17 of the Wire therebetween to form asection having end portions 18 and a relatively narrow medial portion19, as viewed in FIGURE 3. Locating grooves 21 are formed in oppositesides of the wire stock by the forming punches 12 and 13 to receivelocator members 2222 carried by the punches.

The chain of connected link plate sections 17 moves step-by-step fromthe first station 6 to the second station 7 where they are successivelyflattened between a mashing punch 23 and the anvil 11 and formed withcircular cavities 24, each section being accurately located under thepunch 24 by reciprocable locators 26 actuated by hydraulic cylinders 27.

The chain of connected sections 17 moves from the lead bath tank 4 intoa quenching tank 28 filled with parafiin oil at a temperature ofapproximately F. The chain of connected link plate sections 17 thenmoves through a third station 30 comprising a pin hole punch 29 and adie 31 adapted to punch two pin holes 32 in each section, each sectionbeing held in fixed position during the punching operation by means ofopposing locators 33 actuated by hydraulic cylinders 34 for engagementin the locating grooves 21.

After the hole punching operation, the chain of connected link platesections 17 moves step-by-step into a reciprocable shear device 36 wherethe sections 17 are successively separated from the chain of linksections to complete the formation of finished link plates 37 which thenpass through a degreasing device 38.

While a hotworking process for forming link plates has been shown anddescribed, it will be understood that the wire 2 may be formed in a coldcondition while passing through the several forming stations.

I claim:

1. The method of progressively forming wire stock to fabricate chainlink plates, which comprises forming notches at spaced intervals inopposite sides of the wire stock to provide a chain of connected linksections, compressing each link section to provide large end portionsconnected by a relatively narrow medial portion, mashing each linksection to provide flat parallel top and bottom surfaces thereon,punching pin holes in said enlarged end portions, and successivelyshearing each link section from the chain of link sections, the wirestock being maintained in a molten lead bath at a temperature up toapproximately 1000 F. during formation of the chain of link sections.

2. A method according to claim 1 in which the wire stock is quenched ina tank of liquid maintained at a temperature of approximately 120 F.

3. A method according to claim 2 in which the pin holes are punched inthe link sections after the quenching operation.

4. A method according to claim 1 wherein the wire stock is moved throughthe molten bath and thence through liquid parafiin oil at a temperatureof the order of 120 F.

5. A method according to claim 4 wherein the pin holes u 3,410,031 I; g

ar punched in the link sect QQ after'they have passed- 1 V FQRE N W outof contact w1th the paraflin 011. 859,387 1/ 1961 Great Britai Referen Cd UNITED STATES PATENTS 5 RLES W. LANHAM, Primary Examiner.

1,670,758 5/1928 Witherow 5935 G. P. "CROSBY, Assistant Examiner.1,881,631 10/1932 Jewett 59-35

